Systematic Evaluation of HLA-G 3’Untranslated Region Variants in Locally Advanced, Non-Metastatic Breast Cancer Patients: UTR-1, 2 or UTR-4 are Predictors for Therapy and Disease Outcome

Abstract

Despite major improvements in diagnostics and therapy in early as well as in locally advanced breast cancer (LABC), metastatic relapse occurs in about 20% of patients, often explained by early micro-metastatic spread into bone marrow by disseminated tumor cells (DTC). Although neoadjuvant chemotherapy (NACT) has been a successful tool to improve overall survival (OS), there is growing evidence that various environmental factors like the non-classical human leukocyte antigen-G (HLA-G) promotes cancer invasiveness and metastatic progression. HLA-G expression is associated with regulatory elements targeting certain single-nucleotide polymorphisms (SNP) in the HLA-G 3’ untranslated region (UTR), which arrange as haplotypes. Here, we systematically evaluated the impact of HLA-G 3’UTR polymorphisms on disease status, on the presence of DTC, on soluble HLA-G levels, and on therapy and disease outcome in non-metastatic LABC patients. Although haplotype frequencies were similar in patients (n = 142) and controls (n = 204), univariate analysis revealed that the UTR-7 haplotype was related to patients with low tumor burden, whereas UTR-4 was associated with tumor sizes >T1. Furthermore, UTR-4 was associated with the presence of DTC, but UTR-3 and UTR-7 were related to absence of DTC. Additionally, increased levels of soluble HLA-G molecules were found in patients carrying UTR-7. Regarding therapy and disease outcome, univariate and multivariate analysis highlighted UTR-1 or UTR-2 as a prognostic parameter indicative for a beneficial course of disease in terms of complete response towards NACT or progression-free survival (PFS). At variance, UTR-4 was an independent risk factor for a reduced OS besides already known parameters. Taken into account the most common HLA-G 3’UTR haplotypes (UTR-1–UTR-7, UTR-18), deduction of the UTR-1/2/4 haplotypes to specific SNPs revealed that the +3003C variant, unique for UTR-4, seemed to favor a detrimental disease outcome, while the +3187G and +3196G variants, unique for UTR-1 or UTR-2, were prognostic parameters for a beneficial course of disease. In conclusion, these data suggest that the HLA-G 3’UTR variants +3003C, +3187G, and +3196G are promising candidates for the prediction of therapy and disease outcome in LABC patients.

HLA-G 3’UTR polymorphism diplotypes and soluble HLA-G plasma levels impact cervical cancer susceptibility and prognosis

“…HLA-G is an inhibitory checkpoint molecule, which is highly expressed in gynecological cancers, such as cervical cancer ( 3 , 4 , 7 – 10 ), ovarian cancer ( 20 ), breast cancer ( 21 , 22 ), and endometrial cancer ( 23 ). It’s known that virus-infected cells and malignant cells escape the host’s immune surveillance by inducing the expression of HLA-G ( 4 – 6 , 10 ).…”

Elevated sHLA-G plasma levels post chemotherapy combined with ILT-2 rs10416697C allele status of the sHLA-G-related receptor predict poorest disease outcome in early triple-negative breast cancer patients

“…Cytospin preparations, containing single cell suspensions derived from mononuclear bone marrow cells of TNBC patients, were used for genomic DNA extraction by QIAamp DNA Blood Mini Kit (Qiagen, Hilden, Germany) according to manufacturer’s instructions. Typing of HLA-G 3’ UTR haplotype was performed by polymerase chain reaction (PCR) as previously described ( 39 , 43 ). Typing of the ILT-2 rs10416697C/G SNPs located distant from ILT-2 gene promoter region was determined by a Taqman assay (ThermoFisher Scientific) according to manufacturer’s instructions.…”

“…In non-metastatic locally advanced BC patients including a total of 18% TNBC patients, our study group recently demonstrated that high levels of vesicular-bound HLA-G before CT were associated with stem cell like CTC as well as with early disease progression ( 38 ). Moreover, certain HLA-G 3’ UTR haplotypes were found to predict therapy and disease outcome in that patient cohort ( 39 ).…”

The prognostic differences and the effect of postmastectomy radiotherapy between post‐chemotherapy ypT1‐2ypN1 and de novo pT1‐2N1 breast cancer

“…The value of chemotherapy for node‐positive BC patients has been well established 3 . Neoadjuvant chemotherapy (NAC) can downstage primary tumors and axillary nodes, increase the eligibility for breast‐conserving surgery and improve the survival of patients with locally advanced BC 4–9 . However, it remains unclear whether there are the same survival and prognosis between patients with the same stages after NAC and at initial diagnosis, especially in pT1‐2N1M0 BC 10 .…”

“… 3 Neoadjuvant chemotherapy (NAC) can downstage primary tumors and axillary nodes, increase the eligibility for breast‐conserving surgery and improve the survival of patients with locally advanced BC. 4 , 5 , 6 , 7 , 8 , 9 However, it remains unclear whether there are the same survival and prognosis between patients with the same stages after NAC and at initial diagnosis, especially in pT1‐2N1M0 BC. 10 Previous studies showed that the 5‐year LRFS, DMFS and OS rates of patients with de novo T1‐2N1 BC were 86.8%, 91.0%, and 83.8%, respectively, 11 yet rare studies have explored the survival outcomes of post‐chemotherapy ypT1‐2ypN1 BC patients.…”